Backpack



FIG. 1 is a front and top perspective view of a backpack, showing my new design;

FIG. 2 is a rear and bottom perspective view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a rear elevation view thereof;

FIG. 5 is a left side elevation view thereof;

FIG. 6 is a right side elevation view thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof;

FIG. 9 is an enlarged view of a portion indicated with numeric 9 in FIG. 1;

FIG. 10 is an enlarged view of a portion indicated with numeric 10 in FIG. 1; and,

FIG. 11 is an enlarged view of a porfion indicated with numeric 11 in FIG. 2.

The broken lines in the figures illustrate portions of the backpack that form no part of the claimed design. The dash dot dash lines in FIGS. 1, 2, 9, 10 and 11 are for the purpose of depicting the cut line of the enlarged view and form no part of the claim. 

CLAIM The ornamental design for a backpack, as shown and described. 